sounds ridiculous to me_________________www.informationclearinghouse.info
May you re-discover what the poor in 18th century France discovered, that rich people's heads can be mechanically separated from their shoulders if they refuse to listen to reason.

while i have gone to lengths to avoid writes a person also should not be afraid to use their ssd. it should last a long time._________________www.informationclearinghouse.info
May you re-discover what the poor in 18th century France discovered, that rich people's heads can be mechanically separated from their shoulders if they refuse to listen to reason.

Yes, SATA3 (6Gb/sec) is needed to get this high... Make sure you're using a good cable and a SATA3 port. There's only 2 on my z68 board..._________________Intel Core i7 2700K@ 4.1GHz/HD3000 graphics/8GB DDR3/180GB SSDWhat am I supposed to be advocating?

Yes, SATA3 (6Gb/sec) is needed to get this high... Make sure you're using a good cable and a SATA3 port. There's only 2 on my z68 board...

i looked at the specs for agility 3 and intel 520 at newegg, very close._________________www.informationclearinghouse.info
May you re-discover what the poor in 18th century France discovered, that rich people's heads can be mechanically separated from their shoulders if they refuse to listen to reason.

I do have to say something is strange - how old is the AsRock 890GM board?
It's weird that it has 5 SATA 6Gb ports but my Z68 (Gigabyte Z68AP-D3) only has two... Apparently Intel thinks sata 6Gb ports are hard to attach and therefore only offers 2... Not sure if it's the motherboard limiting the speed or not.

How are the SATA6Gb attached to the cpu, does it go through the southbridge (bad)? When you're using hdparm to test, it should not care about fragmentation much, as fragmentation really affects small writes.

steffie: what CPU do you have? Curious how much the CPU determines the cached read speeds versus the chipset/disk..._________________Intel Core i7 2700K@ 4.1GHz/HD3000 graphics/8GB DDR3/180GB SSDWhat am I supposed to be advocating?

How are the SATA6Gb attached to the cpu, does it go through the southbridge (bad)? When you're using hdparm to test, it should not care about fragmentation much, as fragmentation really affects small writes.

When you partitioned the drive did you ensure it was aligned to 4k as oppose to 512?
by default fdisk will partition assuming a 512b sector size, which is valid for old HDD

Newer HDD as well as SSD have sector sizes of 4096 (so they don't run out of indexing). Thing is if you partition the drive without taking this into consideration and the partition/s are NOT aligned to these clusters you end up in a situation where reads/writes require spanning 2 sectors to complete resulting in additional commands being issued to the controller_________________the table is made from wood. forget what you learnt, the table is made from carbon. forget what you learnt, the table is made from protons. forget what you learnt, the table is made from quarks. forget what you learnt, the table is good for shagging on

The port connection issue is very technical but it boils down to the latency and bottlenecks involved when passing data through the channels. Now I don't know too much about AMD Hypertransport unfortunately, only have some rudimentary knowledge about Intel QPI, but I have to assume they have some similarities. The SATA controllers can be connected to the first level QPI where bandwidths are highest but there are a limited number of connections. One possibility to increase the number of connections is to put it on a bridge to multiplex more connections, usually the southbridge. There's latency and delays involved there which will slow down throughput.

The sector fragmentation is an interesting possibility but if you hdparm on the raw device like /dev/sda, etc., this should be aligned to the first sector/sector 0, which should be aligned to any sector size, or at least I would hope it to be the case... With newer versions of fdisk starting at sector 2048 this should be aligned to 4096 byte-sectors as long as your partitions are a multiple of 4096 bytes._________________Intel Core i7 2700K@ 4.1GHz/HD3000 graphics/8GB DDR3/180GB SSDWhat am I supposed to be advocating?

I think it already is, but you can't really redo without erasing everything (though gparted might be able to do something).

Start sector 2048 (versus 63, because old versions of fdisk aligned to "track" which makes sense for very old disks) is a multiple of 4096 since 2048*512 is a multiple of 4096 - it's the 256th 4096 sector.

I'm still convinced it's a motherboard issue at the moment._________________Intel Core i7 2700K@ 4.1GHz/HD3000 graphics/8GB DDR3/180GB SSDWhat am I supposed to be advocating?

cat /sys/block/sda/queue/physical_block_size
4096
cat /sys/block/sda/queue/logical_block_size
512_________________the table is made from wood. forget what you learnt, the table is made from carbon. forget what you learnt, the table is made from protons. forget what you learnt, the table is made from quarks. forget what you learnt, the table is good for shagging on

There are lots of litature out there detailing why having an unaligned can cause issues_________________the table is made from wood. forget what you learnt, the table is made from carbon. forget what you learnt, the table is made from protons. forget what you learnt, the table is made from quarks. forget what you learnt, the table is good for shagging on

Imagine if hard drives "Bus Errors" when someone does an unaligned access...

(sorry about this bad, obscure joke related to how some CPUs will bus error when doing unaligned accesses. Once again this is a performance related issue on CPUs too! Then again the bus errors were meant to make people rewrite their code, maybe we need to do this for HDDs too...)_________________Intel Core i7 2700K@ 4.1GHz/HD3000 graphics/8GB DDR3/180GB SSDWhat am I supposed to be advocating?